Fuel economizing system and apparatus



- Dec. 2, 1941. G. .L BYRNE I FUEL ECONOMIZING SYSTEM AND APPARATUS 2 SheetsL-Sheet l Filed July l2, 1939 ...En v6 mgwwmq, SEK@ INVENTOR GE .BY/2N;-

ATToRNEY Dec. 2, 1941. G. J. BYRNE FUL ECONOMIZING SYSTEM AND APPARATUS Filed July l2, 1959 2 Sheets-Sheet 2 wg bv buv.

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INVENTOR v lGo, @E J BVR/v5 BY /V Tmw . m v6. l ATTORNEY v Patented Dec. 2, 1941 l FUEL EcoNoMrziNG SYSTEM APPARATUS George J. Byrne, Chicago, Ill., assignor to Byrnes Hot Draft Corporation, a corporation of Illinois Application July 12, 1939, Serial No. 283,943

(Cl. 11o-49) 11 Claims.

rihis invention relates to smoke eliminating and fuel economizing systems and apparatus primarily adapted for steam boiler furnaces and the like and, more particularly, to apparatuses applicable to and a system ormethod for operation of steam boiler or other furnaces with which steam may be generated for any purpose, whereby a fuel such as soft coal including cheap or poor grades thereof may be burned more efficiently and completely and with less loss through smoke and unburned gases than under other or similar conditions of operation without the application of the invention thereto. In certain aspects the invention may be considered as supplemental to or an improvement upon the invention disclosed in my prior Patent 2,183,184 dated December 12, 1939.

The primary object of the invention, of course, is to provide an apparatus and a system or vmethod for the more efficient combustion of soft coal including poor grades thereof and for the reduction if not the complete elimination of smoke and ncornpletely burned gases and the losses incurred therethrough and, to such ends, other and more specific objects including:

The provision of means for recycling or returning a substantial portion of the exhaust products going to the furnace stack, particularly during initial periods of operation of the furnace, to the fire after mixing such returned combustion products with fresh air and steam;

The provision of a positive or forced feed of fresh air for mixing with combustible parts of furnace exhaust products rather than to rely upon a gravity or merely induced flow of air for such purposes;

The provision of an arrangement of apparatus whereby the particles of combustible material and combustible gases carried in the exhaust products from a furnace are thoroughly commingled and brought into intimate and combustible association with an amount of oxygen sufficient to effect complete combustion thereof;

The provision of means to pre-heat the fresh air used to effect combustion of the combustible parts of the smoke or exhaust products from the furnace, since it would appear that preheating the air accelerates or aids in obtaining an inti* mate or close contact between the smoke particles and the oxygen of the air mixed therewith;

The provision of a system of automatic control over the supply of air, steam and exhaust products being mixed and fed to the intake Adraft side of the furnace; v

The provision of safety means to prevent the lso expensive apparatus of the character mentioned and the provision of various novelfeatures in addition lto those above generally mentioned, for

the attainment of the foregoing and other objects as will become apparent after reading the following description and claims alone or when taken in conjunction with the accompanying drawings in which:

Fig. 1 is a schematic illustration of one embodiment of the invention as applied to a steam boiler furnace the view being in side elevation.

Fig. 2 lis also a schematic view, infront elevation of the furnace, boiler and apparatus of Fig. l.

Fig. 3 is a diagrammatic illustration of the electricalcontrol system utilized in operating the apparatus Vshown in Figs. l and 2 and,

Figs. ,4 and 5', respectively, are transverse and longitudinal sectional views of fragments of the mixing or agitating chamber Within which the furnace exhaust products or portions thereof are intimately mixed or homogenized and contacted by and with steam and fresh air. l

In Figs. 1 and 2 a furnace 2 equipped with a boiler as indicated by the legend on Fig. 1, has `a draft intaker 3 into the ash pit below the furnace grates (notshown). vAre door through which the fuel is charged into the fire is designated 4 and a pair of doors 5 for access to the boiler o r boiler tubes for cleaning and other purposes are designated 5. The boiler may be provided with the usual steam pressure gauge 6, water level gauge (not shown) and with Such other accessories as may be Yuseful or desirable, as will be understood. The exhaust gases from thewfur-v nace pass into the furnace breechrig (not shown) and thence through the exhaust pipe or exhaust vstack l and thence into the chimney'or smoke stack 8 through which they pass to the atmosphere. 'l f Suitably hinged as at 9 to be projected to varying extents (through pre-adjustment) into and across the path of products of combustionpa'ssing from the furnace and up'the smoke stack 8, is a damper or valve Il to which at I2, is pivoted an operating rod I3 in turn pivoted at I4 toone arm of l5 of a bell-crank lever which is pvoted` j at I6 and has its other arm I 'I connectedthrough aV pin and slot connection with an extension [il of the core (not shown) of a solenoid I 9.` The flow of exhaust products from escaping into the 55 Solenoid il! may Vbe supported onbraclk'ets ,2|"at5 ,tion which in. turn will project the damper or -'valve II into the smoke stack or chimney to deflect products of combustion into the duct 22, the arrangement being such that the valve does not completely close 01T the chimney ow. Of course through various well known means of adjustment or otherwise the extent of projection of the valve I I into the chimney flue may be controlled so as to increase or decrease the quantity of products of combustion deflected into the duct 22. When the solenoid is deenergized a spring (not shown) and gravity or gravity alone may serve to close the valve I I over the end of duct 22.

Products of combustion may ow through the duct 22 into a pipe or duct 23 which leads to a mixing or agitating chamber 24 within which combustible particles and combustible gases contained in the furnace exhaust products are intimately and homogeneously intermingled and contacted with steam and fresh air. Aiterbeing mixed withv steam and fresh air in chamber 24 the products of combustion are drawn from the chamber through a duct 25 by a blower 26 driven by an electric motor 21 and are discharged through a duct 28 into the draft intake side of the furnace, i. e., through the ash pit or beneath the grate, in any suitable manner.

Disposed in the duct 28 is a valve or damper .29 which may be hinged at 3l and pivotally connected with one end of an operating link 32 the other end of which is pivotally connected to an operating arm 33 carried by an extension 34 of a core of a solenoid 35 which may be carried on a bracket 36 secured to the'duct 28. The arrangement is such that when the solenoid 25 is energized the valve 29 is moved to the position shown in the dotted lines and when deenergized a spring or other means effects movement of the valve 29 to a position transversely of the duct 28 thereby to close the same.

Leading from the boiler is a steam line 31 in which a solenoid operated valve 38 is disposed and which is connected with a steam header 39 which may run substantially the full length of the mixing chamber 24. Leading from the header 39 are a plurality of pipes or tubes 4I which are carried through and terminate inside of the walls of the mixing chamber 24, as more clearly represented in Figs. 4 and 5, terminating a short distance within the mixing chamber inside of what may be termed nozzle members 42 which may be secured by welding or otherwise in apertures formed in the Walls in the mixing chamber and through which apertures the steam jet pipes are projected. Suitable plugs close the apertures. It Will be noted that the nozzle members 42 are inclined inwardly and toward the direction of ow of the products of combustion into and through the mixing chamber and similarly the inner ends of the steam jet pipes 4I are inclined in conformity therewith but terminate short of the inner ends of the nozzle members. It will also be noted that there are a plurality of these nozzles and steam jets disposed longitudinally and circumferentially of the mixing chamber at suitably spaced places from one another in each direction. The number and arrangement Vof nozzles and jets may be varied as circumstances may dictate but should be suflicient to provide a thorough mixing or homogenizin'g of air and steam with the products of combustion owing through the chamber. The amount of steam and air needed may be adjusted in accordance with the rate of ow of products of combustion through the chamber, the character of the products of combustion and other factors as will be understood.

Also disposed within each of the nozzle members 42 is a tube or jet 43 which is adapted to supply a jet of compressed air with the steam into the mixing chamber 24. The several jet tubes 43 are connected to a header or tank 44 which is arranged in close proximity to or against the wall of the mixing chamber and similarly in close proximity to or against the steam header 39 thereby to pre-heat the air being supplied to the chamber 24 substantially to equalize the temperature of the air with the temperature of the exhaust products flowing through the chamber. The tank may be equipped with a pressure gauge 45, if desired, and receives compressed air through pipe 46 from a compressor 41 driven by an electric motor 48. A housing 49 of suitable construction and arrangement to permit accessibility to the mixing chamber, may be placed around the steam header, the air tank, the blower and its motor, and the compressor and its motor, to keep these parts of the apparatus clean and free from dust and dirt.

In Fig. 3 a diagram of the electrical control system is illustrated and reference will now be made to this control system. Wires 5I and 52 leading from a source of current supply may be connected (one or both) through a Mercoid switch control generally designated 53, with a line represented by wires 54 and 55 from which leads 56, 51, 58, 59 and 6I, all in parallel, are tapped respectively to the blower motor 21, the solenoid control 35 for the valve II, the compressor motor 48, the solenoid control for the valve 38, and the intake damper solenoid control I9. 'I'he Mercoid control switch mechanism which may be of any of several types well known onv the market, may be arranged for control either through the pressure of steam generated within the boiler or in the line 31, or it may be,- arranged for thermostatic or temperature operation as will be understood. Its location is relatively immaterial except that it should reflect some characteristic of the steam in the boiler or the condition of the re in the furnace, as will also be understood. The air tank 44 may also have a connection 62 leading to a rheostat or pressure actuated control switch 63 of any suitable character mounted von top of the compressor motor whereby to maintain a substantially constant pressure on the air in the air tank and ilowing to the jets 43, and such switch may be arranged to reduce the speed of the motor 48 or to shut 01T the motor if the pressure in the air tank increases beyond a predetermined pint.

In operation, as when starting a fire in the furnace under the boiler, the arrangement may be such that the valve II, is in closed position over the end of duct 22 so that for the time being products of combustion ow up Aand out the chimney or stack 8. In this case the Mercoid control switch is open so that neither the motor 21 nor the.motor 48 is in operation and the solenoids I9, 35 and 38 are deenergized and the valves controlled by the solenoids are in closed position. When a pre-determined temperature'is attained in the boiler or a predeter mined pressure as -forinsta-nce 1 lb. -cf steam is generated in the boiler, the Mercoid control switch may close thereby energizing all vof vthe solenoids and opening thevalves they control, while at the same time the 'motors 21 and 43 are started to operate the blower 26 and to furnish compressed air into the mixing chamber. With the valve 33 open steam is -admitted into the header 39, and through each of the jets 4|, into the products of combustion being drawn into Vducts 22 and 23 and through the mixing cham- -ber 24, duct 25 and yblower 26 from which Ythe mixture is blown through -duct 28 lto the draft intake of the furnace. During the initial period ofoperation a separate draft intake (not shown) may -be opened, -or if desired, a separate circuit may be provided for the blower and compressor motors 2'! and 348, respectively, to supply su- -cient air vfor the linitial combustion period, 'but during suchtime the valve ll will remain closed over the end of duct 22 and no steam will be supplied to the mixing chamber. With such an arrangement, automatic or manual control means maybe provided for connecting and dis- -connecting the secondary circuit with and from the motors '2 and 48 when the steam pressure `or temperature rises to the point where the control system of Fig. -3 comes into operation.

Assuming that the Mercoid contro-1 has been uset to close the circuit when the steam pressure in Ithe boiler reaches 1 1b. (gauge) or a temperature -corresponding to such pressure if the switch operates thermostatically, a substantial amount of the smoke and other products of combustion will be deflected by the opening of valve Il into the ducts 22 and 23 and drawn into mixing chamber 24 by the action of the blower 26. At the same time the opening of solenoid valve 38 admits steam into header A39 and the compressor 41 supplies compressed air into tank 44 and thence into the mixing chamber. The jets of compressed air and steamenter the mixing chamber and agitate or produce turbulence of the contents of the mixing chamber and tend to aid in accelerating the velocity of the mixture toward the blower. The turbulence or agitation produced within the mixing chamber practically insures complete mixing of the products of combustion with the air and steam before the mixture reaches the blower which of course may be considered as supplementing the mixing if any additional mixing or homogenizing is necessary. The

-mixture thus prepared is supplied to the furnace beneath the grates (some or all might also be -delivered immediately over the fire within the furnace) with the result that substantially complete combustion of incompletely burned gases and smoke particles .is effected.

After the steam pressure in the boiler or the temperature thereof has reached a predetermined point, as for instance, when the steam pressure reaches 2 pounds (gauge) lwhich is a satisfactory maximum working pressure for ordinary house heating purposes under ordinary conditions, the furnace iiremay be banked during which period there will be relatively little loss in unburned fuel products. Therefore, the Mercoid control is set to open the circuit to the motors 2 and 48 and to the solenoids I9, 38 and S at the desired pressure in the boiler or temperature thereof. Opening the circuit will close the valves Il and 2'9'in the `ue and intake duct and also will close the steam control valve k38. The operation of thefuel economizerand smoke eliminator then ceases until-the steamy pressure or lboiler temperature drops to 'a preldetermined point, sa'y f1 pound pressure A'(gauge') at which time the Mercoid control Aagainicl'oses the circuit and the cycle of operationspreviously described `'is repeated. Under some circumstances -it maybe `desirable to set the Mercoid control to vclose -the'circuit when the'furnace is being started V"in which'cas'e the Valves Il, 29 and v38 open and `remainopen until some predetersatisfactory as when it is being supplied thereto. 'The admixture of steam-with .air tothe combustible products exhausting from the furnace .apparentlyhas several effects. In the first place :thefinjectionjof the steam and the fresh air in jet fform yproduces a mechanical mixing or turbulence within the mixing chamber which, of course, tends toresult in a thoroughly homogeneous mixture of oxygen and Vcombustible particles andY gases thereby enabling the particles and gases to be burned completely when lreach- Second, .the steam seems to act as an aid or catalyst whereby the oxygen may contact the combustible particlesand gases although vat a temperature vbelow the point of ignition or chemical combination therewith and also to associate itself in `some Way with the incompletely burned products of combustion such,'as, for instance, carbon monoxide with theresult that upon -thepassage of theimixture vto vthe zone of combustion in the furnacethe combustible particles of the smoke, i. e.A the carbon, and other combustib-le products, such as carbonmoncxide gas, are substantially completely consumed or oxidized. The steam lmay also tend to combine chemically with some of the hot products of combustion to form, by dissociation or'otherwise, combustible gases. I

have found, for instance, that the mixture as it issuesfrom the mixing chamber will burn freely with a blueflame when brought to kindling temperature, assuming 'that suiiicient air to support combustion has been supplied to the mixture. And a third effect seems to be of Value, namely, the pre-heating of the air w-hich is jetted into the mixing chamber. The pre-heating seems to have a materially beneficial effect `even beyond thefeffect of the retention and addition offso many B. t. u.s, as the pre-heated air appears to mix the more readily and the more Vthoroughly and `the more intimately with the combustion products including the gases and combustible particles 'flowing into the chamber, than it does if not vpre-heated.'

I am unable to explainthese actions, reactions and phenomena which appear to take place and o n which I-have attempted to theorize in this description, but I do know `that remarkable ordinary firing, has been obtained.

While I have illustrated and described apreferred embodiment of the invention and the pre- 'ferred method of operation, it will be appreciated that-theinventionis susceptible of various `other embodiments and thatv other --methods of operation may be utilized without departing from the invention spirit and the scope ofthe appended claims.

I claim:

l. In an apparatus of the character described, means providing a mixing chamber, means including a plurality of nozzles for supplying steam and air under pressure into said mixing chamber for commingling with products of combustion contained in said chamber, said` nozzles being arranged at spaced places circumferentially of the chamber, means for connecting said chamber with a furnace outlet, means for connecting said vchamber with the draft inlet of a furnace, and

means operative at a predetermined steam pressure for cutting off the supply of steam and air from said chamber.

2. In an apparatus of the character described, means providing a mixing chamber, means for supplying steam and air to said mixing chamber for commingling with products of combustion contained in said chamber, means for connecting said chamber with a furnace outlet, and means Vfor connecting said chamber with the draft inlet of a furnace, valve means for opening and closing the connection between said chamber and draft inlet, and means operated by variations in boiler pressure during operation of the furnace for controlling the supply of air and steam to said chamber and simultaneously operating said valve means, said valve means being open when steam and air are being supplied to said chamber.

3. In an apparatus of the character described, means providing a mixing chamber, means for -supplying steam and air to said mixing chamber for commingling with products of combustion contained in said chamber, means for connecting said chamber with a furnace outlet, means for connecting said chamber with the draft inlet of a furnace, blower means for feeding the mixture from said chamber into the draft inlet of the furnace, valve means for opening and closing the connection between said chamber and the .said draft inlet, and means operative upon the attainment of a predetermined steam pressure for automatically cutting olf the supply of steam and air to said chamber and` for substantially simultaneously closing said valve.

4. In an apparatus of the character described, means providing a mixing chamber having an linlet and an outlet for exhaust stack products from a furnace, duct means for connecting the inlet of said chamber with the exhaust stack of a furnace, duct means for connecting the outlet of said chamber with the draft intake of l a furnace, means including a plurality of nozzles for supplying steam and air to said chamber and from a plurality of places into said chamber whereby intimately to mix with exhaust products from the furnace, and means for pre-heating the air supplied to said chamber.

5. In anv apparatus of the character described, means providing a mixing chamber having an inlet and an outlet for exhaust stack products from a furnace, duct means for connecting the inlet cf -said chamber with the exhaust stack of a furnace, duct means for connecting the outlet of said chamber with the draft intake of va furnace, means including a plurality of nozzles for supplying steam and air to said chamber and said nozzles delivering steam and air into said chamber from a plurality of places longitudinally and circumferentially of said chamber whereby intimately to mix with exhaust products from the furnace, and means for pre-heating the air supplied to said chamber.

6. In an apparatus of the character described, means providing a mixing chamber having an inlet and an outlet for exhaust stack products from a furnace, duct means for connecting the inlet of said chamber with the exhaust stack of a furnace, duct means for connecting the outlet of said chamber with the draft intake of a furnace, and means including a plurality of nozzles for supplying steam and air to said chamber and said nozzles being arranged and disposed tof deliver air and steam into said chamber from a plurality of places longitudinally and circumferentially of said chamber whereby intimately to mix with exhaust products from the furnace.

'7. In an apparatus of the character described, means providing a mixing chamber having an inlet and an outlet for exhaust stack products from a furnace, duct means for connecting the inlet of said chamber with the exhaust stack of a furnace, duct means for connecting the outlet of said chamber with the draft intake of a furnace, means including a plurality of nozzles for supplying steam and air under pressure to said chamber and from a plurality of places longitudinally and circumferentially of said chamber whereby intimately to mix with exhaust products from the furnace, means for shuttingoff the steam supply to said nozzles, and means automatically operative to close said duct means to said draft intake substantially simultaneously with operation of said steam supply shut-off means.

8. In an apparatus of the character described, a duct for connecting the exhaust stack of a furnace with the draft inlet thereof, means for defiecting exhaust products from said stack into said duct, means for supplying air and steam into said duct for mixing with products of combustion therein, means for causing a forced flow through said duct to said draft inlet, means for opening and closing said duct to said draft inlet, and means automatically operative to render said deecting means inoperative to deflect exhaust products into said duct upon the closing of said duct to said draft inlet and, substantially simultaneously, to effect cessation of operation of said means for causing a forced flow through said duct.

9. In an apparatus of the character described, means providing a mixing chamber having an inlet and outlet, duct means for connecting the Vinlet of said chamber with the exhaust stack of a furnace, electric motor operated means` for deflecting exhaust products from said stack toward said chamber, duct means for connecting the outlet of said chamber with the draft inlet of a furnace, electric motor operated means for causing a forced flow of exhaust products from said stack to said draft intake through said duct means and chamber, electric motor operated means for supplying compressed air into 4inlet of said chamber with the exhaust stack of .a furnace, means for deecting exhaust products from said stack toward said chamber, duct means for connecting the outlet of said chamber with the draft inlet of a furnace, means for causing a forced flow of exhaust products from said stack to said draft intake through said duct means and chamber, means for supplying preheated air and steam into said chamber and into the exhaust products passing through said chamber, valve means for closing said duct means to said draft inlet, means for stopping the supply of air and steam to said chamber, and means automatically operative to close said valve means upon cessation of the supply of steam and air to said chamber.

11. In an apparatus of the character described, means providing a mixing chamber having an inlet and outlet, duct means for connecting the inlet of said chamber with the exhaust stack of a furnace, motor operated means for deecting exhaust products from said stack toward said chamber, duct means for connecting the outlet of said chamber with the draft inlet of a furnace, motor driven means for causing a forced flow of exhaust products from said stack to said draft intake through said duct means and chamber, means for supplying preheated air into said chamber and into the exhaust products passing through said chamber, motor controlled means for supplying steam to the products in said chamber, motor operated valve means for closing said duct means to said draft inlet, and control means operative upon a predetermined rise in steam pressure for stopping the supply of air and steam to said chamber, for rendering said def'lecting means inoperative and for automatically closing said valve means.

GEORGE J. BYRNE. 

